A gas turbine engine includes a fan section and a core engine. The core engine includes serial axial flow relationship, a high pressure compressor to compress an airflow entering the core engine, a combustor in which a mixture of fuel and the compressed air is burned to generate a propulsive gas flow, and a high pressure turbine which is rotated by the propulsive gas flow and which is connected by a shaft to drive the high pressure compressor. A typical bypass turbofan engine adds a low pressure turbine aft of the high pressure turbine which drives a fan of the fan section located forward of the high pressure compressor. A splitter aft of the fan divides fan flow exiting the fan into core engine flow and bypass flow around the core engine.
The fan section includes one or more stages of fan rotor blades and a strut assembly. The strut assembly includes circumferentially spaced struts mounted to a hub at radially inner ends and to an outer case at radially outer ends. The outer case defines a circular shape, such that a circular flowpath surface is defined for a flowpath through the fan section. The case is typically circular in nature in order to withstand relatively high internal pressures. A circular case is known to be well-suited for withstanding these relatively high internal pressures (e.g., a delta pressure load of at least about fifty pounds per square inch).
The strut assembly must be capable of withstanding relatively large forces generated during operation of the gas turbine engine. These forces may include static forces from a weight of the various components of the gas turbine engine, as well as static forces generated during, e.g., in certain maneuvers of an aircraft including the gas turbine engine. Additionally, the strut assembly may be exposed to dynamic forced during, e.g., a fan blade out event, in which case a resulting asymmetrically balanced fan subjects the strut assembly to relatively large dynamic loads. The strut assembly is typically formed in a relatively robust manner in order to withstand the static and dynamic forces. However, such may lead to a relatively heavy strut assembly for the gas turbine engine.
Accordingly, a strut assembly better able to withstand the static and dynamic forces would be useful. Moreover, a strut assembly better able to withstand the static and dynamic forces, while reducing an overall weight of the strut assembly, would be particularly beneficial.